摘 要 : 电子密码锁以其卓越的安全性与使用的灵活性,具有广阔的应用前景,在诸多 场合已逐渐取代了传统的机械锁。本文以 AT89C51 单片机为控制芯片,以 LCD1602 为显 示单元,利用串行存储器 AT24C02 来实现密码的存储和修改,结合硬件电路设计与软件 编程技术,给出一种电子密码锁控制系统实现方案,可实现密码的输入和修改、信息的显 示、键盘的锁定、系统报警、开锁和闭锁等多方面功能,并对方案进行了仿真验证及硬件 实现。该方案改变了现有密码锁控制系统的密码量少,安全性差等缺点,所设计系统结构 简单,操作方便,性能稳定,功能易扩展,可广泛应用于各种门控系统。65403
毕业论文关键词: 电子密码锁,单片机,AT89C51
Abstract:The electronic password lock with its outstanding safety and the use flexibility, has the broad application prospect, in many situations already substituted the tradition mechanical lock gradually. The AT89C51 single-chip microcomputer as the control chip, LCD1602 display
unit, to realize the storage and modify the password using the application of AT24C02 serial memory, combined with the hardware circuit design and software programming technology, give an electronic password lock control system realization plan, realize the password input and modification, information display, keyboard lock, alarm system, unlocking and locking on function and the program were the results of the simulation and hardware achieve. This scheme has changed the existing password lock control system password less, poor security weaknesses, the design system has the advantages of simple structure, convenient operation, stable performance, easy expansion of functions, widely used in all kinds of gating system.
Keywords: electronic password lock, Single-chip microcomputer, AT89C51
目 录
1 绪论 5
1.1 电子密码锁简介 5
1.2 电子密码锁设计的背景及意义 5
1.3 电子密码锁的现状及发展趋势 5
2 总体设计 6
2.1 设计分析 6
2.2 系统结构 7
3 硬件电路设计 7
3.1 单片机接口分配 7
3.2 单片机最小系统设计 8
3.2.1 时钟电路 8
3.2.2 复位电路 8
3.2.3 最小系统 9
3.3 矩阵键盘设计 9
3.4 LCD 显示模块设计 10
3.5 掉电存储模块 12
3.5.1 I2C 总线 12
3.5.2 AT24C02 简介 13
3.6 开锁机构 14
3.7 报警机构 15
3.8 硬件综合设计 15
4 软件设计 16
4.1 软件总体设计 16
4.2 键盘扫描子程序 17
4.3 显示模块子程序 20
4.4 掉电存储子程序 22
4.4.1 写操作方式 22
4.4.2 读操作方式